/Engine/Source/Runtime/Engine/Public/LevelInstance/LevelInstanceSubsystem.h
void ForEachLevelInstanceChild ( [ILevelInstanceInterface](API\Runtime\Engine\LevelInstance\ILevelInstanceInterface) * LevelInstance, bool bRecursive, [TFunctionRef](API\Runtime\Core\GenericPlatform\TFunctionRef)< bool([ILevelInstanceInterface](API\Runtime\Engine\LevelInstance\ILevelInstanceInterface) *)> Operation ) const